From 1992297b0810a42d78ec7b4de15304eb0489fd97 Mon Sep 17 00:00:00 2001 From: Michal Suchanek Date: Thu, 5 May 2016 17:31:48 -0700 Subject: [PATCH 02/10] mtd: m25p80: return amount of data transferred or error in read/write Add checking of SPI transfer errors and return them from read/write functions. Also return the amount of data transferred. Signed-off-by: Michal Suchanek Signed-off-by: Brian Norris Acked-by: Michal Suchanek Tested-by: Michal Suchanek --- drivers/mtd/devices/m25p80.c | 29 +++++++++++++++++++++-------- 1 file changed, 21 insertions(+), 8 deletions(-) --- a/drivers/mtd/devices/m25p80.c +++ b/drivers/mtd/devices/m25p80.c @@ -81,6 +81,7 @@ static ssize_t m25p80_write(struct spi_n struct spi_transfer t[2] = {}; struct spi_message m; int cmd_sz = m25p_cmdsz(nor); + ssize_t ret; spi_message_init(&m); @@ -98,10 +99,15 @@ static ssize_t m25p80_write(struct spi_n t[1].len = len; spi_message_add_tail(&t[1], &m); - spi_sync(spi, &m); + ret = spi_sync(spi, &m); + if (ret) + return ret; - *retlen += m.actual_length - cmd_sz; - return 0; + ret = m.actual_length - cmd_sz; + if (ret < 0) + return -EIO; + *retlen += ret; + return ret; } static inline unsigned int m25p80_rx_nbits(struct spi_nor *nor) @@ -128,13 +134,13 @@ static ssize_t m25p80_read(struct spi_no struct spi_transfer t[2]; struct spi_message m; unsigned int dummy = nor->read_dummy; + ssize_t ret; /* convert the dummy cycles to the number of bytes */ dummy /= 8; if (spi_flash_read_supported(spi)) { struct spi_flash_read_message msg; - int ret; memset(&msg, 0, sizeof(msg)); @@ -151,7 +157,9 @@ static ssize_t m25p80_read(struct spi_no ret = spi_flash_read(spi, &msg); *retlen = msg.retlen; - return ret; + if (ret < 0) + return ret; + return msg.retlen; } spi_message_init(&m); @@ -169,10 +177,15 @@ static ssize_t m25p80_read(struct spi_no t[1].len = len; spi_message_add_tail(&t[1], &m); - spi_sync(spi, &m); + ret = spi_sync(spi, &m); + if (ret) + return ret; - *retlen = m.actual_length - m25p_cmdsz(nor) - dummy; - return 0; + ret = m.actual_length - m25p_cmdsz(nor) - dummy; + if (ret < 0) + return -EIO; + *retlen += ret; + return ret; } static int m25p80_erase(struct spi_nor *nor, loff_t offset)